1. Field
This disclosure relates to a poly(imide-amide) copolymer, a method for preparing a poly(imide-amide) copolymer, and to an article including a poly(imide-amide) copolymer.
2. Description of the Related Art
A flexible display, which is not restricted by time and place, that is thin and flexible like paper, ultra light, and consumes a small amount of electricity, has been increasingly in demand as a display for visualizing various information and delivering it to the users. The flexible display may be realized by using a flexible substrate, organic and inorganic materials for a low temperature process, flexible electronics, encapsulation, packaging, and the like.
A transparent plastic film for replacing a conventional window cover glass to be used in a flexible display must meet high hardness and optical properties. Hardness may be supplemented by a hard coating layer, but in this case also, a base film having a high tensile modulus renders a final film having a high hardness. Desired optical properties include high light transmittance, low haze, low yellowness index, and the like.
Thus, there remains a need for polymers having excellent optical and mechanical properties.